<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script>
        var num=0;
        var arr=[66,88,99];
        for (i=0;i<arr.length;i++){
            num+=arr[i];
        }
        console.log(num);
    </script>
</head>
<body>

</body>
</html>